Share-based payments - Additional information (Detail) - USD ($)	12 Months Ended
Dec. 31, 2021	Dec. 31, 2020
Disclosure of terms and conditions of share-based payment arrangement [line items]
Percentage of cancellations employees electing to withdraw their investment shares before vesting of their matching shares	15.00%
Liability for cash-settled awards	$ 6,000,000	$ 7,000,000
Rio Tinto Limited
Disclosure of terms and conditions of share-based payment arrangement [line items]
Percentage of share-based payment charge for plan	100.00%	100.00%
Rio Tinto plc
Disclosure of terms and conditions of share-based payment arrangement [line items]
Percentage of share-based payment charge for plan	100.00%	100.00%
Performance share plans
Disclosure of terms and conditions of share-based payment arrangement [line items]
Description of vesting requirements for share-based payment arrangement	Forfeitures prior to vesting are assumed at
Percentage of forfeitures, prior to vesting, on outstanding awards	5.00%	5.00%
Performance share plans \| Rio Tinto Limited
Disclosure of terms and conditions of share-based payment arrangement [line items]
Cash-settled awards outstanding	27,476	15,164
Performance share plans \| Rio Tinto plc
Disclosure of terms and conditions of share-based payment arrangement [line items]
Cash-settled awards outstanding	20,548
Liability for cash-settled awards	$ 2,000,000
Performance share plans \| Rio Tinto plc \| Top of range
Disclosure of terms and conditions of share-based payment arrangement [line items]
Cash-settled awards outstanding		48,191
Liability for cash-settled awards		$ 3,000,000
Management share awards
Disclosure of terms and conditions of share-based payment arrangement [line items]
Description of vesting requirements for share-based payment arrangement	The vesting of these awards is dependent on service conditions being met
Percentage of forfeitures, prior to vesting, on outstanding awards	7.00%	7.00%
Share incentive plan
Disclosure of terms and conditions of share-based payment arrangement [line items]
Liability for cash-settled awards	$ 4,000,000
Share incentive plan \| Top of range
Disclosure of terms and conditions of share-based payment arrangement [line items]
Liability for cash-settled awards		$ 4,000,000
Share incentive plan \| Rio Tinto Limited
Disclosure of terms and conditions of share-based payment arrangement [line items]
Cash-settled awards outstanding	12,217	14,878
Share incentive plan \| Rio Tinto plc
Disclosure of terms and conditions of share-based payment arrangement [line items]
Cash-settled awards outstanding	89,239	89,253
– Global Employee Share Plan
Disclosure of terms and conditions of share-based payment arrangement [line items]
Description of vesting requirements for share-based payment arrangement	The vesting of these matching awards is dependent on service conditions being met and the continued holding of investment shares by the participant until vesting.
Percentage of forfeitures, prior to vesting, on outstanding awards	5.00%	5.00%
– Bonus Deferral Awards
Disclosure of terms and conditions of share-based payment arrangement [line items]
Description of vesting requirements for share-based payment arrangement	The vesting of these awards is dependent only on service conditions being met.
Percentage of forfeitures, prior to vesting, on outstanding awards	3.00%	3.00%
– Bonus Deferral Awards \| Other Executives
Disclosure of terms and conditions of share-based payment arrangement [line items]
Percentage of bonus deferral	25.00%
– Bonus Deferral Awards \| Executive Directors And Product Group Executives
Disclosure of terms and conditions of share-based payment arrangement [line items]
Description of vesting requirements for share-based payment arrangement	50% of the bonuses
Percentage of bonus deferral	50.00%

The description of the vesting requirements for a type of share-based payment arrangement that existed at any time during the period. An entity with substantially similar types of share-based payment arrangements may aggregate this information. [Refer: Share-based payment arrangements [member]]

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name IFRS
-Number 2
-IssueDate 2021-01-01
-Paragraph 45
-Subparagraph a
-URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IFRS&num=2&code=ifrs-tx-2021-en-r&anchor=para_45_a&doctype=Standard
-URIDate 2021-03-24

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- Definition

Line items represent concepts included in a table. These concepts are used to disclose reportable information associated with members defined in one or many axes of the table.

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- Definition

The amount of liabilities arising from share-based payment transactions. Share-based payment transactions are transactions in which the entity: (a) receives goods or services from the supplier of those goods or services (including an employee) in a share-based payment arrangement; or (b) incurs an obligation to settle the transaction with the supplier in a share-based payment arrangement when another group entity receives those goods or services. [Refer: Share-based payment arrangements [member]]

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name IFRS
-Number 2
-IssueDate 2021-01-01
-Paragraph 51
-Subparagraph b
-Clause i
-URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IFRS&num=2&code=ifrs-tx-2021-en-r&anchor=para_51_b_i&doctype=Standard
-URIDate 2021-03-24

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- Definition

Number of shares cash-settled awards outstanding in share-based payment arrangement.

+ References

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- Definition

Percentage Of Bonus Deferral

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- Definition

Percentage of cancellations employees electing to withdraw their investment shares before vesting.

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- Definition

Percentage of forfeitures, prior to vesting, on outstanding awards.

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- Definition

Percentage of share-based payment charge for plan.

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